In a semiconductor device manufacturing process in which a laminated structure of an integrated circuit is formed on the surface of, for example, a semiconductor wafer (hereinafter, referred to as a “wafer”) as a substrate, a liquid processing such as, for example, chemical liquid cleaning or wet etching is performed. When removing liquid remaining on the surface of the wafer using the liquid processing, a drying method using a processing fluid in a supercritical state has been recently used (see, e.g., Japanese Patent Laid-Open Publication No. 2013-012538).
When the drying processing of the substrate is performed by supplying the processing fluid in the supercritical state into a processing container from a supercritical fluid supply source, for example, the phenomenon that particles attached to the surfaces of members inside the processing container travel upward and are attached to the surface of the processed substrate frequently occurs.